1. Field of the Invention
The present invention relates to an optical disc drive, and more particularly, to a slim type optical disc drive that has a simple construction, and allows a tray to be more easily carried and a disc to be more easily loaded and unloaded.
2. Description of the Related Art
As is generally known in the art, an optical disc drive records and reproduces information using light incident on a recording medium such as a compact disc (CD) or a digital versatile disc (DVD). Optical disc drives are generally used in computers and especially in notebook computers, a slim type optical disc drive of very small thickness is used.
FIG. 1 is an exploded perspective view schematically illustrating the construction of a conventional slim type optical disc drive. FIG. 2A is a vertical transverse section schematically illustrating the slim type optical disc drive of FIG. 1, loaded with a disc, and FIG. 2B is an enlarged view of the part A of FIG. 2A.
Referring to FIGS. 1 through 2B, the conventional slim type optical disc drive includes a housing 10 having a lower case 11 and an upper case 12, and a tray 20 mounted in the housing 10 to slide in and out of the housing 10. A main base 30 is assembled with the tray 20 using vibration-proof rubber members 32 interposed between the tray 20 and the main base 30. A spindle motor 40 rotates a disc D. An optical pickup unit 50 records and reproduces data onto and from the rotating disc D. A pickup transport (not shown) carries the optical pickup unit 50 along the radius of the disc D. The spindle motor 40, the optical pickup unit 50, and the pickup transport are installed to the main base 30. A turntable 42, onto which the disc D is mounted, is provided on the spindle motor 40. The spindle motor 40 and the optical pickup unit 50 are installed in the tray 20 so that they also slide in and out of the housing 10 with the tray 20.
Further, the optical disc drive is provided with tray guiding units 28 which guide the movement of the tray 20 as described above. The tray guiding units 28 include rail assembling portions 22 formed at both sides of the tray 20, sliding rails 24 slidably assembled with the rail assembling portions 22, and rail guides 26 fixed at both corners of the lower case 11 so as to slidably support the sliding rails 24. A locking apparatus (not shown) is used to lock the tray 20 into the housing 10, and an ejector (not shown) is used to eject the tray 20 from the housing 10. The locking apparatus and the ejector are disposed in the housing 10 and on the lower surface of the tray 20. An eject button 62 to operate the ejector is arranged on the front face bezel 60 of the tray 20.
A main printed circuit board 70 provides an interface between the optical disc drive and external devices and is fixed to the lower case 11. Further, the main printed circuit board 70, the spindle motor 40 and the optical pickup unit 50 are electrically interconnected through a flexible printed circuit 72.
When the disc D is loaded into the slim type optical disc drive constructed as described above, after the tray 20 is drawn out of the housing 10, the disc D is seated on a turntable 42 and then pushed into the housing 10. Then, the locking apparatus is operated to lock the tray 20 into the housing 10. When the disc D is unloaded, the eject button 62 is pressed to operate the ejector, which pushes the tray 20 out of the housing 10.
However, in the conventional slim type optical disc drive, the spindle motor 40, the optical pickup unit 50, and the pickup transport are all installed in the tray 20, making the tray 20 heavy and complicated as well as thick. Further, the extra weight of the spindle motor 40, the optical pickup unit 50, and the pickup transport, which slide out together with the tray 20, prevent the smooth movement of the tray 20 and require the tray 20 and the tray guiding units 28 to be relatively thick. Therefore, there are limits to slimming the conventional optical disc drive.
Further, when designing the complicated construction described above, it is difficult to maintain a gap between the disc D and the tray 20, which is necessary to prevent the disc D from contacting the tray 20 due to vibrations. Moreover, when attempting to reduce a vibration of the spindle motor 40, which is the main source of the vibrations, it is difficult to find the vibration transmission path in the tray 20, which further complicates the design for reducing the vibrations.
Additionally, the flexible printed circuit 72 which connects the fixed main printed circuit board 70 to the movable spindle motor 40 and the optical pickup unit 50 may contact the tray 20 and wear away while the tray 20 is moving in and out of the housing, reducing durability or causing faults.